Asking out a girl and giving my phone number?

I am 95% a girl is interested in me. I won't be seeing her after tomorrow as I am leaving town so was going to ask her out.

I was going to say that: 'I go for green tea often- you should come with me next time!' If she says yes then I will ask if she knows where to find me. I will then ask for her hand and slip my phone number on a piece of paper in there, smile and leave.